Our present invention relates to a steering wheel lock.
In German patent document DE 86 21 592 U1 and DE 195 35 437 A1, actuators for locks are described which are particularly suitable for use in automotive vehicle applications, e.g. for door locks, and which utilize a lock actuator in the form of an electric motor and gearing connecting that motor with the mechanical lock unit.
Motor vehicles frequently require, in addition, steering wheel locks which prevent rotation of the steering wheel until an ignition key is inserted into the ignition switch and/or an electronic or other unit is actuated in preparation for vehicle operation. In the past problems have been encountered with the relatively long period of time required for unlocking the steering wheel.
It is, therefore, an object of the present invention to provide an improved steering wheel lock which eliminates the aforedescribed problem with respect to the reaction time in unlocking.
Another object is to provide a steering wheel lock which is compatible with the lock control systems of an automotive vehicle but which can provide rapid transition between locking and unlocking of a steering wheel.
Another object of this invention is to provide a rapidly acting, reliable and simple steering wheel long device which can be actuated electrically and is, therefore, compatible with electrical systems of modern motor vehicles.
These objects and others which will become apparent hereinafter are attained, in accordance with the invention in a steering wheel lock which has an electrical drive unit for a rotatable spindle on which a nut is axially displaceable by the screwthread of the spindle and which, in turn, entrains a detent disk. The detent disk can be rotated into a locking position to allow the locking pin to block the steering wheel.
The nut can be braced by a spring which rotates the spindle to return the nut into its starting position. That spring can be received in a drive gear for the spindle and can be stressed or tensioned by rotation of the spindle into the locking position and can expand once the spindle has reached its locking position.
The detent disk can have a projection, which can be an extension rib or a pin-like projection engageable in a camming track, e.g. a groove, for displacing the detent disk into its locking position. The groove can have an axial portion transitioning into a transverse portion for effecting rotation of the detent disk upon axial displacement or translation thereof by the nut. The pin can be held in its unlocked position by a latch operated by a latch mechanism and that latch can include a slider whose pin blocks the spindle. More specifically, the steering wheel lock can comprise:
a rotary spindle formed with a thread;
a drive unit operatively connected to the rotary spindle for driving same;
a locking nut on the spindle and engaging the thread;
a detent disk in the spindle entrained by the nut and rotatable from an unlocking position into a locking position upon entrainment by the nut; and
a locking pin operated by the detent disk for locking a steering wheel upon rotation of the detent disk from the unlocking position into the locking position.